Authors
Petya Boycheva
Medical University „Prof. D-r Paraskev Stoyanov“, Faculty of Pharmacy, Department of Biology, Varna, Bulgaria
Dobri Ivanov
Medical University „Prof. D-r Paraskev Stoyanov“, Faculty of Pharmacy, Department of Biology, Varna, Bulgaria
Galina Yaneva
Medical University „Prof. D-r Paraskev Stoyanov“, Faculty of Pharmacy, Department of Biology, Varna, Bulgaria